In close cooperation with Versalis, Pepperl+Fuchs developed the technical definition of the customer's solution. 117 motor operated valves (MOVs), located around the entire explosion-hazardous area (ca. 2 km²), now form the new fire protection system. Due to the extremely high requirements for safety critical application inside the petrochemical production plant, every digital communication path is installed with triple redundancy (main line, secondary line, service line). A centralized ring topology helps to bridge distances between the broadly placed motor operated valves.
Seven remote I/O stations by Pepperl+Fuchs, with redundant power supplies and bus couplers, are connected to the ring topology via Ethernet/Modbus TCP-IP and fiber optic converters. To further increase safety, the extinguishing system is redundantly layed out. Binary inputs monitor position feedback and overall status of the fire protection system. The entire remote I/O system is built into a hardy stainless steel enclosure.
During factory inspection and acceptance check, the solution impressed with achieved time savings, as the remote I/O functionalities allowed a quick examination of the entire ring. Each software and hardware mechanism and each ring were tested. Testing routines affected remote I/O technologies as well as digital systems, so all simulations were run with the help of the PACTware tool. The large amount of data generated turned out to be very useful to get a quick overview of the status of the whole system structure.
The new system now provides a modern, diagnostic, and predictive monitoring of the valve position of the extinguishing valves directly over the control system. This reduces plant downtime and ensures a higher production efficiency. When a valve gets stuck, operators receive a diagnostic notification from the control system, which allows them to immediately initiate a targeted service deployment. Time consuming on-site inspection walks by service technicians to each valve are no longer needed to test their functional capability.
Compared to the previously installed point-to-point topology, Versalis now saves several kilometers of wiring with the new remote I/O based network solution. After all, 50 % – 60 % less cabling is needed inside the chemical plant. Pepperl+Fuchs' solution turned out to be a true efficiency booster in several ways while at the same time ensuring a maximum of safety and availability.